Picture talk: Use of images attracts more eyeballs. It is humanitarian. Even if it is a data centric post or a theoretical one, have an image that speaks significantly for your post.
Newsletter: Newsletter is a great way to keep your audience glued on to all that is happening on your blog. It is best way to know who your loyal audience is.
E-commerce bloggers must carefully write keeping their audience in mind. Everything you post on your blog will speak for your product or service. Your interaction with bloggers in comments and otherwise will give you a direction.